Prior line circuit switching network connections have been effected on a per line basis wherein numerous dedicated switching components have been employed for each line to accomplish prespecified connection functions. These prior systems have employed special purpose relays which inherently limit the speed and versatility of the system. Moreover, these prior systems have employed compensation networks which, while decreasing the degree of mismatch also impair the signal power.
As seen for example in U.S. Pat. No. 4,161,633, microcomputers have been employed in interface circuits to effect interface supervision between a switching network and a subscriber line. However, such systems have required a plurality of separate control leads from the microcomputer to be connected to each line circuit and the individual relays to those lines. These systems also have relied on analog control signals. While such systems have provided improved capabilities, they have not yet provided a fully integrated interface system for control and information transfer.